Regenerative hydrorefining of petroleum crude oil



United States Patent Oflfice 3,293,172 Patented Dec. 20, 1966 3,293,172REGENERATIV E HYDROREFINING OF PETROLEUM CRUDE OIL William K. T. Gleim,Island Lake, 111., assignor to Universal Oil Products Company, DesPlaines, 111., a corporation of Delaware No Drawing. Filed Apr. 29,1964, Ser. No. 363,628 16 Claims. (Cl. 208-264) The present inventionrelates to a regenerative process for hydrorefining of petroleum crudeoil, heavy vacuum gas oil, crude tower bottoms, vacuum tower bottoms,visbreaker product efiiuent, heavy cycle stocks, and other high-boilinghydrocarbon fractions and/or distillates. More specifically, the presentinvention is directed toward a catalytic slurry process forhydrorefining heavy hydrocarbonaceous material severely contaminated bythe presence of excessive quantities of deleterious substances. Thepresent process encompasses continuous regeneration and recirculation ofthe catalyst employed therein.

In one of its various embodiments, the present inveution involves aprocess for efiecting the decontamination, or hydrorefining, of a heavyhydrocarbon charge stock for the primary purpose of efiiecting thedestructive removal of nitrogenous and sulfurous compounds, andparticularly for the conversion of the pentane-insoluble portion of suchcharge stock into useful pentane-soluble hydrocarbon products. Crudepetroleum oil, and other heavy hydrocarbon fractions and/or distillates,boiling at temperatures above the gasoline and middle-distillate boilingranges, such as crude tower bottoms, vacuum gas oil, heavy cycle stocks,black oil, etc., generally contain nitrogenous and sulfurous compoundsin large quantities; In addition, these high-boiling hydrocarbonfractions contain quantities of metallic contaminants which exhibit thetendency to exert detrimental effects upon the catalyst utilized invarious processes to which the crude oil, or portion thereof, or otherheavy hydrocarbonaceous material, is ultimately subjected. The morecommon of such metallic contaminants are nickel and vanadium, althoughother metals including iron, lead, arsenic, copper, etc., may bepresent. These metallic contaminants, as well as others, may be presentwithin the hydrocarbonaceous material in a variety of forms: they mayexist therein as metal oxides or as sulfides, introduced into the crudeoil as metallic scale or particles; they may be in the form of solublesalts of such metals; usually, however, these contaminants are found toexist as organo-metallic compounds of high molecular weight, such asmetal porphyrins and various derivatives thereof. Where the metalliccontaminants are present as oxide or sulfide scale, they may be removed,at least in part by a relatively simple filtering technique, thewater-soluble salts of such metals being removable by washing andsubsequent dehydration. However, a much more severe treatment isgenerally required to remove, or destroy, the organo-metallic compounds,and to the extent that the resulting heavy hydrocarbonaceous fractionbecomes suitable for further processing. Notwithstanding that the totalconcentration of these contaminants, for example metallic porphyrins, isrelatively small, often less than about p.p.m., calculated as theelemental metals, subsequent processing techniques are readily adverselyafiected thereby. For example, when a hydrocarbon charge stock,containing metals in excess of about 3.0 p.p.m., is subjected to acracking process for the purpose of producing lower-boiling, normallyliquid hydrocarbons, the metals become deposited upon the catalystemployed, steadily increasing in quantity until such time as thecomposition of the catalytic composite is changed to the extent thatundesirable results are obtained.

In addition to the contaminating influences in the form of nitrogenousand sulfurous compounds, and metallic complexes, crude oils and otherheavy hydrocarbon fractions generally consists of a significant quantityof highboiling, pentane-insoluble material. For example, a Wyoming sourcrude oil, having a gravity of 232 API at 60 F., not only iscontaminated by about 2.8% by weight of sulfur, approximately 2700p.p.m. of total nitrogen, a total of about 100 p.p.m. of metallicporphyrins (computed as elemental nickel and vanadium), but alsocontains a high-boiling, pentane-insoluble asphaltenic fraction in anamount of about 8.39% by weight. Similarly, and a much more difficultcharge stock to convert into valuable, useful normally liquidhydrocarbons, a crude-tower bottoms product having a gravity, API at 60F., of 14.3, is contaminated by the presence of about 3.0% by weight ofsulfur, 3830 p.p.m. of total nitrogen, p.p.m. of total metals and about10.93% by weight of asphaltenic compounds. Asphaltenes are highmolecular weight hydrocarbons considered to be coke-precursors havingthe tendency to become immediately deposited within the reaction zoneand other process equipment, and onto the catalytic composite in theform of a gummy, high molecular weight residue. Since this in efiectconstitutes a large loss of charge stock, it is economically desirableto convert such asphaltenes into pentane-soluble liquid hydrocarbonfractions. Furthermore, the presence of excessive quantities ofasphaltenes appears to inhibit the activity of a catalytic compositewith respect to the removal of sulfur and nitrogen by conversion thereofto hydrogen sulfide, ammonia and hydrocarbons.

The object of the present invention is to provide a more efiicientprocess for hydrorefining, or decontaminating, such petroleum crudeoils, than the processes currently being employed. A fixed-bed catalyticprocess, or a fixed-fluidized bed process for the hydrorefining ofhighly contaminated heavy hydrocarbonaceous material, is virtuallyprecluded due to the difiiculty in maintaining the catalyst in an activecondition. Various moving-bed processes employing catalytically activemetals deposited upon refractory inorganic oxide materials, such assilica and/or alumina, are extremely erosive, thereby causing plantmaintenance to become diflicult and expensive. The present inventionteaches the preparation of a colloidally dispersed, unsupportedcatalytic component useful in a regenerative slurry process. The presentprocess yields a liquid hydrocarbon product which is more suitable forfurther processing, without experiencing the difficulties otherwiseresulting from the presence of the above-described contaminants. Thecatalyst of the present invention is particularly advantageous foreffecting the removal of the organo-metallic complexes, withoutsignificant product yield loss while simultaneously convertingpentane-insoluble material into pentane-soluble liquid hydrocarbons,notwithstanding the high concentrations of the other contaminatinginfluences.

Therefore, in a broad embodiment, the present invention relates to aregenerative process for hydrorefining a hydrocarbon charge stock, whichprocess comprises the steps of: (a) admixing said charge stock with atleast one organo-metallic compound selected from the metals of GroupVI-B having an atomic number greater than 24, and Group V-B of thePeriodic Table; (b) decomposing said organo-metallic compound in saidcharge stock and reacting the resulting colloidal suspension withhydrogen; (c) separating the resulting reaction mixture to provide ahydrorefined liquid product and a catalystcontaining sludge; (d)dissolving the organic-soluble mazerial contained in said sludge andcombining the resultng solution with said charge stock; (e) treating therenaining portion of said sludge with a sulfurous comaound selected fromthe group consisting of sulfur mono: :hloride, sulfur dichloride and amixture thereof; (f) separating the resulting insoluble coke from saidSludge; and, (g) admixing the remainder of said sludge, containing theaforesaid metals, with said charge stock.

In particular, the present invention encompasses a process forhydrorefining a hydrocarbon charge stock, which process comprises stepsof: (a) admixing said :harge stock with at least one carbonyl of themetals of Group VI-B having an atomic number greater than 24, andGroupV-B of the Periodic Table; (b) heating the resulting mixture at atemperature less than about 310 C., and for a time sufficient todecompose said carbonyl within said charge stock; (c) reacting theresultingcolloidal suspension with hydrogen at a temperature within therange of from about 225 C. to about 500 C. and

under a pressure of from about 500 to about 5000 p.s.i.g.;-

( d) separating the resulting reaction mixture to provide a hydrorefinedliquid product and a catalyst-containing sludge; (e) dissolving theorganic-soluble material contained in said sludge and combining theresulting solution with said charge stock; (f) treating the remainingportion of said sludge, at a temperature within the range of from about300 C. to about 500 C., with a solution of from about 0.1% to about25.0% by weight of a sulfurous compound selected from the groupconsisting of sulfur monochloride, sulfur dichloride and a mixturethereof; (g) separating the resulting insoluble coke from thethustreated sludge; and, (h) combining the resulting solidfree remainderof said sludge, containing the aforesaid metals, with said hydrocarboncharge stock and reacting the resulting colloidal suspension withhydrogen as aforesaid.

A more limited embodiment of the present invention encompasses a processfor hydrorefining a petroleum crude oil containing pentane-insolubleasphaltenes, which process comprises the steps of: (a) admixing saidcrude oil with at least one beta-diketone complex of the metals of GroupVI-B having an atomic number greater than 24, and Group V-B of thePeriodic Table; (b) decomposing said beta-diketone complex in saidcharge stock at a temperature less than about 310 C. and reacting theresulting colloidal suspension with hydrogen and added hydrogen sulfideat a temperature within the range of from about 225 C. to about 500 C.and under a pressure of from about 500 to about 5000 p.s.i.g.; (c)separating the resulting reaction mixture to provide a hydrorefinedliquid product and a catalyst-containing sludge; (d) dissolving theorganic-soluble material contained in said sludge and combining theresulting solution with said charge stock; (e) treating the remainingportion of said sludge, at a temperature within the range of from about300 C. to about 500 C., with a solution of from about 0.1% to about25.0% by weight of a sulfurous compound selected from the groupconsisting of sulfur monochloride, sulfur dichloride and a mixturethereof; (f) separating the resulting insoluble coke from thethus-treated sludge; and, (g) combining the resulting solid-freeremainder of said sludge, containing the aforesaid metals, with saidcharge stock, and reacting the resulting colloidal suspension withhydrogen and added hydrogen sulfide as aforesaid.

From the foregoing embodiments, it is readily ascertained that themethod of the present invention involves the preparation of acolloidally-dispersed catalytic component utilizing metals selected fromthe group consisting of the metals of Group VI-B and having an atomicnumber greater than 24, and Group V-B of the Periodic Table. Therefore,the catalyst prepared in accordance with the method of the presentinvention, may comprise one or more metallic components from the groupof vanadium, niobium, tantalum, molybdenum, tungsten, and

. 4 mixtures of two or more. It will be noted that the metal selectedfrom Group VLB, namely molybdenum and/ or tungsten, has an atomic numbergreater than 24. It has been found that organo-chromium compounds do notyield comparable results upon subsequent reaction with hydrogen, and inparticular do not elfect a suitable degree of conversion of thepentane-insoluble material and the destructive removal of theorgano-metallic contaminants such as the nickel and/or vanadiumporphyrins. The catalyst is prepared by initially dissolving anorganometallic complex of the selected metal, or metals, in thehydrocarbon charge stock containing a pentane-insoluble fraction whichis to be converted into soluble hydrocarbons. The quantity of theorgano-metallic compounds employed is such that the colloidalsuspension, or dispersion, resulting when the organo-metallic compoundis decomposed in the hydrocarbon charge stock, comprises from'about 1.0%to about 10.0% by weight, calculated as if the metal existed in theelemental state. Suitable organo-metallic compounds include molybdenumblue, molybdenum hexacarbonyl, phosphomolybdic acid, molybdylacetylacetonate, silicomolybdic acid, tungsten hexacarbonyl,phosphotungstic acid, tungsten acetylacetonate, silicotungstic acid,tungsten ethylxanthate, vanadium carbonyl, phosphovanadic acid, vanadylacetylacetonate, vanadyl ethylxanthate, other carbonyls, heteropolyacids, beta-diketone complexes, etc.

Briefly, the process is effected :by initially mixing the desiredquantity of the organo-metallic compound, for example, a mixture ofphosphomolybdic acid and vanadyl acetylacetonate in the hydrocarboncharge stock, in amounts such that the resulting colloidal suspension,or dispersion contains from about 1.0% to 10.0% by weight of molybdenumand vanadium, calculated as the elements thereof. In order to facilitatethe formation of the colloidal suspension, upon decomposition of theorganometallic compound, it is often advisable to form a solution ofsuch organo-metallic compound in a suitable solvent such =as an alcohol,a ketone, an ester, etc., adding such solution dropwise to thehydrocarbon charge stock. The resulting mixture is then heated,preferably in the absence of free hydrogen and other well-known reducingagents, at a temperature less than about 310 C. for a time sufiicient toeffect the decomposition of the organometallic compound, and to removethe solvent by distillation, thereby forming a colloidal suspension, ordispersion of the metallic component within the hydrocarbon chargestock. The colloidal dispersion is then passed into a suitable reactionzone maintained at a temperature within the range of from about 225 C.to about 500 C. and under a hydrogen pressure Within the range of about500 to about 5000 p.s.i.g. The presence of added hydrogen sulfide,within the hydrogen atmosphere, has been found to enhance the catalyticactivity of most of the organometallic compounds, and particularly thebeta-diketone complexes of vanadium and tungsten, and such hydrogensulfide is added in an amount within the range of about 1.0% to about15.0% by volume prior to effecting the hydroretining reactions. I

In order to maintain the catalyst in its decomposed form, which isbelieved to be either as the elemental metal, or as a lower oxidethereof, it is necessary that the reaction zone be substantiallycompletely free from carbon monoxide. Following the decomposition of atleast some of the foregoing organo-metallic compounds, such asmolybdenum hexacarbonyl, some carbon monoxide will be present in thegaseous phase; this is readily removed by venting prior to passing themixture into the reaction zone. Where some of the carbon monoxide isdissolved in the liquid phase, it is preferred to remove the same bysuitable stripping means. When effected in a continuous manner, theprocess may be conducted in either upward flow or downward flow. Thenormally liquid hydrocarbons are separated from the total reaction zoneproduct efiluent by any suitable means, for example,

through the utilization of a centrifuge, or settling tanks, theremaining catalyst-containing sludge being treated as hereinafter setforth.

The catalyst-containing sludge is a viscous fluid consisting of thecatalytic metals, originally dispersed in the charge stock, unconvertedasphaltenic material, soluble hydrocarbons, porphyrinic materialcontaining nickel and vanadium, coke and heavy carbonaceous material,etc. I have found that the unconverted asphaltenic material consists ofthe 10.0% to about 20.0% by weight of the originally-present asphalteneswhich are significantly more resistant to conversion, and cause aninordinately large proportion of the difficulties experienced when thecrude oil, or heavy fraction derived therefrom, is subjected tohydrorefining and/or hydrocracking. This asphaltenic material is thatwhich possesses the tendency to become virtually immediately transformedinto coke and gummy polymerization material, as a result of which theremaining portion of the asphaltenes fails to come into contact with theactive catalyst components, thereby also becoming increasingly morediflicult to convert. It is, therefore, expedient and economical toremove about 10.0% to about 20.0%, or more, of the total asphaltenicmaterial originally present in the hydrocarbon charge stock, from thecatalyst-containing sludge, prior to recirculating the same to combinewith fresh charge stock. Furthermore, the active catalytic componentsmay then be recombined with the charge stock, to form the colloidalsuspension or dispersion, thereby effecting additional refining of thecharge stock.

Following the separation of the normally liquid hydrocarbons from thecatalyst-containing sludge, the latter is treated with a suitableorganic solvent for the purpose of dissolving residual organic-solublematerial such as the pentane-soluble hydrocarbon products resulting fromthe conversion of the pentane-insoluble asphaltenic compounds originallypresent in the petroleum crude oil. Any well-known organic solvent maybe employed for the dissolution of the organic-soluble material in thecatalystcontaining sludge; suitable solvents include, therefore,pentane, benzene, hexane, heptane, toluene, etc. The resulting solutionmay be subjected to further reaction with hydrogen by recycling the sameto combine with the fresh hydrocarbon charge stock. The remainingportion of the catalyst-containing sludge is then treated, in accordancewith the present invention, with a sulfurous compound selected from thegroup consisting of sulfur monochloride, sulfur dichloride and a mixturethereof. The unconverted asphaltenic material is at least in partconverted into insoluble coke. Such conversion may be readily elfectedat a relatively low temperature within the range of from about 250 C. toabout 450 C. The sulfur chloride is generally employed in an amount offrom about 0.1% to about 25.0% by weight of the material to be treated.An unexpected advantage is afforded, through the use of the statedsulfur chlorides, in that, at lower temperatures of about 100 C. toabout 300 C., the organo-metallic contaminants are subject todestructive removal, such that the metals take on a soluble form, andare thus separated from the heavy hydrocarbon complex. The insolublecoke, resulting from the conversion of the asphaltenes, is separatedfrom the sludge, the resulting substantially solid-free remainder of thesludge being combined with fresh hydrocarbon charge stock, and reactedwith hydrogen as aforesaid. Prior to combining the metals recovered fromthe sludge with the fresh hydrocarbon charge stock, it may be desirableto withdraw at least a portion of such metals, generally from 0.1% toabout 1.0% by weight in order to maintain the highest possible degree ofcatalytic activity. Consequently, a like quantity of metal is added tothe hydrocarbon charge stock as the organo-metallic compound, tocompensate for the quantity of metal removed from the sludge, prior tocombining the latter with said charge stock. The solution recovered fromthe catalyst-containing sludge will contain the original metalliccomponents utilized as the catalyst, and, in addition thereto, at leasta portion of the vanadium originally existing in the charge stock as aporphyrin or a derivative thereof. Since the vanadium component, whencolloidally dispersed within the charge stock, exhibits an acceptabledegree of catalytic activity, very little fresh catalyst is necessary tomaintain catalytic activity, and in many instances the catalyst may beconsidered to be self-sustaining. In any event, the metals recoveredfrom the catalyst containing sludge are combined with fresh hydrocarboncharge stock, the mixture being heated to a temperature not above 310 C.to form the colloidal suspension of dispersion.

Although the process encompassed by the present invention may beelfected in the manner wherein the catalyst-containing sludge is treatedseparately, other processing schemes will be evident to those havingskill in the art of petroleum refining processes, and will beadvantageous in hydrorefining the more severly contaminated chargestocks. For example, when the charge stock is a vacuum tower bottomsproduct having a gravity of l4.7 API at 60 F., and contaminated by 3.18%by weight of sulfur, 3,900 ppm. of total nitrogen, 40 ppm. of nickel,over 400 p.p.m. of vanadium, and containing a high-boiling,pentane-insoluble asphaltenic fraction in an amount of 12.53% by weight,the process readily lends itself to multiple-stage techniques. Thus, thecharge stock may be initially treated with a sulfur chloride at about300 C., to form insoluble coke from about 15.0% of the .asphaltenes andto eliminate at least a portion of the nickel and vanadium porphyrins.After separation of the insoluble coke, the solid-free liquid portioncan be reacted with hydrogen in the presence of the decomposedcatalytically active organo-metallic compound in the manner hereinaboveset forth. The hydrorefined liquid is separated from thecatalyst-containing sludge, the latter then treated with an additionalamount of a sulfur-chloride priolr; to being combined with freshhydrocarbon charge stoc On the other hand, the catalyst-containingsludge can be added to fresh hydrocarbon charge stock, and the mixtureextracted to remove the organic-soluble material. The remaininginsoluble portion of the mixture is then treated at a temperature ofabout 300 C. with a sulfur chloride to convert asphal-tenes intoinsoluble coke which may be readily separated by a centrifuge system orsettling tanks, the supernatant liquid being admixed with theorganic-soluble material, with which mixture the colloidal dispersion ofcatalytic metals will be formed. It is understood that various.modifications are not intended to be removed from the broad scope of thepresent invention as set forth in the specification and appended claims.

Depending upon the particular organo-metallic compound selected as thecatalyst source, the dispersed materia-l is believed to be the elementalmetal or a lower oxide form thereof. Although analytical methods,including X-ray diffraction, have not revealed the precise physicaland/or chemical state of the colloidally disperse-d material, it isbelieved that .the same may exist as a pseudo complex with theasphaltenic compound initial-1y present in the charge stock, or as theelemental metal or an oxide, as hereinbefore stated.

The following examples are given to illustrate the process of thepresent invention, and the effectiveness thereof in convertingpentane-insoluble asphaltenes, while simultaneously effecting theconversion of sulfurous and nitrogeneous compounds into sulfur-free andnitrogenfree hydrocarbons and decreasing significantly the concentrationof organo-metallic contaminants. It is not intended that the presentinvention 'be-unduly limited to the catalyst, charge stock and/oroperating conditions employed in this illustration.

7 Example I The crude oil employed to illustrate the benefits affordedthrough the utilization of the present invention was a Wyoming sourcrude oil, having a gravity of 23.2 API at 60 F., and containing about2.8% by weight of sulfur, approximately 2700 p.p.m. of nitrogen, 18p.p.m. of nickel andv about 81 p.p.m. of vanadium, as metal porphyrins,calculated on the basis of the elemental metal. In addition, the sourcrude oil consisted of about 8.39% by weight of pentane-inso-lubleasphaltenes. As hereinafter indicated, the process of the presentinvention effects the conversion of a significant proportion of suchasphaltenes and to the degree that the same no longer exert adetrimental effect upon further processing. The colloidally dispersedcatalysts were prepared by decomposing the indicated organo-rnetalliccompounds Within the Wyoming sour crude oil, thereafter subjecting themixture to conversion in a rotating autoclave at a temperature of about400 C. and under an imposed hydrogen pressure of about 200 atmospheres.Each of the col loidal suspensions remained in the autoclave as theforegoing conditions for a period of from about four to about eighthours.

Molybdenum hexacarbonyl, in an amount of 23.3 grams, was admixed with200 grams of the Wyoming sour crude, the mixture being charged to therotating autoclave and heated to a temperature at 250 C. for a period ofthree hours. After venting to remove carbon monoxide, the autoclave waspressured to 100 atmospheres with hydro-gen and then heated to atemperature of 400 C. for a period of about four hours, the finalpressure being about 200 atmospheres. The gravity, AP-Iat 60 F., of theresulting normally liquid product eflluent, following separation thereoffrom the catalyst-containing sludge, was 40.1, indicating a significantdegree of conversion to lower-boiling hydrocarbon products. Uponanalysis, this liquid product indicated the continued presence of only7.1 p.p.m. of nitrogen, about 0.02% by weight of sulfur, about 0.10% byweight of pent-aneinsoluble asphaltenes, less than about 0.02 p.p.m. ofnickel and less than about 0.02 p.p.m. of vanadium. When utilizing 23.3grams of molybdenum hexacarbonyl decomposed in situ, in the presence ofhydrogen, the final liquid product was found to contain 347 p.p.m. ofnitrogen compared to 7.1 p.p.m., as hereinabove set forth.

Example II A mixture of the Wyoming sour crude and a colloidallydisperse-d vanadium component was prepared by adding a solution of about42. grams of vanadlyl acetylacetonate, in 500 grams of normal amylalcohol, to 250 grams of the sour Wyoming crude, the mixture beingstirred at a temperature of about 160 C. during the addition: thealcoholic solvent was recovered in an overhead condenser. Thereafter,100 grams of the mixture was sealed in an 850 cc. rotating autoclave andpressured to 100 atmospheres with hydrogen. The contents were heated toa temperature of 400 C., the resulting final pressure being about 200atmospheres, which conditions were maintained for a period of abouteight hours. The bydrorefined product, consisting of normally liquidhydrocarbons, was separated from the catalyst-containing sludge andfound to contain about 0.308% by weight of pentaneinsoluble asphaltenes,less than about 0.03 p.p.m. of nickel, less than about 0.6 p.p.m. ofvanadium and 0.19% by weight of sulfur.

Example III A normal amyl alcohol solution of 23.2 grams of molybdenumhexacarbonyl and 42 grams of vanadyl acetylacetonate is added dropwiseto 450 grams of sour Wyoming crude oil hereinabove described, theresulting mixture being intimately admixed with a vibromixer at atemperature of about 200 C., at which temperature the normal amylalcohol is readily distilled, leaving the molybdenum and vanadiumcomponents colloidally dispersedin the crude oil. The mixture is placedWithin the rotating autoclave and pressured to atmospheres withhydrogen. The temperature is increased to 400 C., the resulting pressurebeing about 200 atmospheres, and the autoclave maintained at theseconditions for a period of about six hours. Following separation fromthe catalyst-containing sludge, the normally liquid product efiluent isfound to have a gravity, API at 60 F., of about 35.5. Upon analysis,this normally liquid product is found to contain less than about 10p.p.m. of nitrogen, less than 0.02% by weight of sulfur, about 0.15% byweight of pentane-insolublc asphaltenes, less than about 0.1 p.p.m. ofnickel and less than about 0.1 p.p.m. of vanadium.

The catalyst-containing sludge, in an amount of about 60 grams, isadmixed with about 60 cc. of benzene, the resulting mixture beingstirred for a period of about one-half hour. Following centrifugalseparation, the henzene solvent and organic-soluble portion of thesludge is admixed with fresh crude oil, the insoluble portion of thesludge, in an amount of about 50 grams being slurried with about 500milliliters of a solution of 10.0 grams of sulfur monochloride. Theinsoluble sludge and sulfur monochloride solution are intimately admixedfor a period of about one hour at a temperature of about 300 C., for thepurpose of converting asphaltenic material to coke and liquidhydrocarbons. The resulting mixture is subjected to centrifugalseparation to remove the coke, follow ing which the supernatant liquidis added dropwise to the mixture of fresh crude oil and benzene solutionof the organic-soluble matter. The centrifuged solids, remaining afterextracting the supernatant liquid therefrom, are in an amount of about5.0 grams.

The mixture of crude oil and benzene-soluble material is heated to atemperature of about C., the supernatant liquid being added dropwisethereto. The resulting colloidal dispersion is placed within therotating autoclave and pressured to 100 atmospheres with hydrogen asbefore. The autoclave is heated to a temperature of 400 C. for a periodof about eight hours, the final pressure being about 200 atmospheres.The total reaction zone product efiiuent is passed into a centrifugalseparator from which the normally liquid hydrocarbon product,substantially free from solids, is removed. This liquid product containsless than about 10 p.p.m. of total nitrogen, less than about 0.10% byweight of sulfur, about 0.02% by weight of pentane-insolubleasphaltenes, less than about 0.10 p.p.m. of nickel and less than about0.10 p.p.m. of vanadium.

Example III A vacuum tower bottoms products having a gravity of 14.7 APIat 60 F., and contaminated by 3.18% by weight of sulfur, 3,900 p.p.m. ofnitrogen, over 450 p.p.m. of nickel and vanadium, is admixed, in anamount of 200 grams, with 40.0 grams (20.0% by weight) of sulfurdichloride, the mixture being placed in a rotating autoclave having acapacity of 1800 cc. The contents of the autoclave are pressured withsufi'icient hydrogen to insure a final pressure of 200 atmospheres afterbeing heated to a temperature of 350 C., these conditions beingmaintained for a period of eight hours. After depressuring and cooling,the contents of the autoclave are subjected to centrifugal separation toremove the insoluble coke particles. The resulting supernatant liquid,upon analysis, indicates about 60.0% removal of the asphaltenicmaterial, and a decrease in the amount of nickel and vanadium to about200 p.p.m.

Phosphomolybdic acid, in an amount of 10.0% by weight (calculated aselemental molybdenum), based upon the quantity of supernatant liquid, isadded dropwise as an isopropyl alcohol solution to the supernatantliquid at a temperature of 160 C. The resulting colloidal suspension isplaced in the rotating autoclave, being maintained therein at atemperature of 425 C. and under a hydrogen pressure of 200 atmospheresfor a period of eight hours. After cooling and depressuring, thecontents of the autoclave are centrifuged to remove thecatalystcontaining sludge from the normally liquid hydrocarbons, thelatter, upon analysis, indicating less than about 0.3 p.p.m. of totalmetals, about 0.1% by weight of sulfur, less than about 10 p.p.m. ofnitrogen and about 0.01% by weight of asphaltenes.

The catalyst-containing sludge is admixed with an additional 200 gramsof vacuum tower bottoms product, the mixture commingled with 20.0% byweight of sulfur monochloride, and placed in the rotating autoclave.After eight hours at a temperature of 350 C. and a hydrogen pressure of200 atmospheres, the contents of the autoclave are centrifuged toprovide a supernatant liquid which, upon analysis, indicates about 60.0%removal of asphaltenic material. An additional amount of phosphomolybdicacid, about 1.0% by weight, as elemental molybdenum, is added to thesupernatant liquid, and the resulting colloidal dispersion is placed inthe autoclave for a period of eight hours at a temperature of 425 C. anda pressure of 200 atmospheres. After separation of thecatalyst-containing sludge, the normally liquid hydrocarbon productindicates a gravity of about 295 API at 60 F., about 0.1% by weight ofsulfur, less than about 10 p.p.m. of total nitrogen and less than about0.01% by weight of asphaltenes.

The foregoing specification and examples clearly illustrate theadvantages afforded the hydrorefining of petroleum crude oils throughthe utilization of the regenerative process of the present invention. Itis of particular interest to note that the concentration of nickel andvanadium, existing as organo-metallic complexes, as well as thepentane-insoluble asphaltenes, have been decreased to a level permittingsubsequent utilization of the crude oil for further processing, and thatat least a portion of the crude oil was converted to lower-boilinghydrocarbon products. Furthermore, the catalyst-containing sludge,following partial conversion to insoluble coke -as hereinbefore setforth, is readily utilized in the formation of a colloidal dispersion tobe reacted with hydrogen in the manner hereinbefore set forth.

I claim as my invention:

1. A regenerative process for hydrorefining a hydrocarhon charge stockcontaining asphaltenes which comprises the steps of:

(a) admixing said charge stock with at least one organo-metalliccompound of a metal selected from the metals of Group VIB having anatomic number greater than 24, and Group V-B of the Periodic Table;

(b) decomposing said organo-metallic compound in said charge stock andreacting the resulting colloidal suspension with hydrogen;

(c) separating the resulting reaction mixture to provide a hydrorefinedliquid product and a catalystcontaining sludge;

(d) contacting the sludge with an organic solvent to dissolve theorganic-soluble material contained in said sludge and combining theresulting solution with said charge stock;

(e) treating the remaining portion of said catalyst-containing sludge ata temperature of from about 100 C. to about 500 C. with a sulfurouscompound selected from the group consisting of sulfur monochloride,sulfur dichloride and a mixture thereof to convert asphaltenes containedtherein to insoluble coke;

(f) separating the resulting insoluble coke from said sludge; and,

(g) admixing the remainder of said sludge, containing the aforesaidmetal, with said charge stock.

2. A process for hydrorefining a hydrocarbon charge stock containingasphaltenes which comprises the steps of:

(a) admixing said charge stock with at least one organo-rnetalliccompound of a metal selected from the metals of Group VI-B having anatomic number greater than 24, and Group V-B of the Periodic Table;

(b) decomposing said organo-metallic compound in said charge stock at atemperature below about 310 C., reacting the resulting colloidalsuspension with hydrogen at a temperature above'about 225 C. and at apressure greater than 500 pounds per square inch gauge;

(c) separating the resulting reaction mixture to provide a hydrorefinedliquid product and a catalystcontaining sludge;

(d) contacting the sludge with an organic solvent to dissolve theorganic-soluble material contained in said sludge and combining theresulting solution with said charge stock;

(e) treating the remaining portion of said sludge at a temperature offrom about C. to about 500 C. with a solution of from about 0.1% toabout 25.0% by weight of a sulfurous compound selected from the groupconsisting of sulfur monochloride, sulfur dichloride and a mixturethereof to convert asphaltenes contained therein to insoluble coke;

(f) separating insoluble coke from the thus-treated sludge; and,

(g) admixing the resulting coke-free remainder of said sludge,containing the aforesaid metal, with said charge stock.

3. The process of claim 2 further characterized in that the mixture ofsaid charge stock and decomposed organometallic compound is reacted withhydrogen at a temperature within the range of from about 225 to about500 C. and under a pressure of from about 500 to 5000 pounds per squareinch gauge.

4. The process of claim 2 further characterized in that saidorgano-metallic compound comprises an organomolybdenum compound.

5. The process of claim 2 further characterized in that saidorgano-metallic compound comprises an organotungstic compound.

6. The process of claim 2 further characterized in that saidorgano-rnet-allic compound comprises an organovanadic compound.

' 7. A processfor hydrorefining a hydrocarbon charge stock containingasphaltenes which comprises the steps of:

(a) admixing said charge stock with at least one carbonyl of a metalselected from the metals of Group VI-B having an atomic number greaterthan 24, I

and Group V-B of the Periodic Table;

(b) heating the resulting mixture at a temperature less than about 310C. and for a time sufficient to decompose said carbonyl within saidcharge stock;

(c) reacting the resulting colloidal suspension with hydrogen at atemperature within the range of from about 225 C. to about 500 C. andunder a pressure of from about 500 to about 5000 pounds per square inchgauge;

(d) separating the resulting reaction mixture to provide a hydrorefinedliquid product and a catalyst-containing sludge;

(e) contacting the sludge with an organic solvent to dissolve theorganic-soluble material contained in said sludge, combining theresulting solution with said charge stock;

(f) treating the remaining portion of said sludge, at a temperaturewithin the range of from about 300 C. to about 500 C., with a solutionof from about 0.1% to about 25 .O% by weight of a sulfurous compoundselected from the group consisting of sulfur 1 1 monochloride, sulfurdichloride and a mixture thereof to convert asphaltenes containedtherein to insoluble .coke;

(g) separating the resulting insoluble coke thus-treated sludge; and,

(h) combining the resulting coke-free remainder of said sludge,containing the aforesaid metal, with said hydrocarbon charge stock andreacting the resultant colloidal suspension with hydrogen as aforesaid.

8. The process of claim 7 further characterized in that aid sludge istreated with said sulfurous compound under I. hydrogen pressure of fromabout 100 to about 300 itmospheres.

9. A process for hydro-refining a petroleum crude oil :ontainingpentaue-insoluble asphaltenes which comprises he steps of:

(a) admixing said crude oil with at least one heteropoly acid of a metalselected from the metals of Group VI-B having an atomic number greaterthan 24, and Group V-B of the Periodic Table;

(b) heating the resulting mixture at 'a. temperature less than about 310C. and for a time Sufficient to decompose said heteropoly acid in saidcharge stock;

() reacting the rtsulting colloidal suspension with hydrogen at atemperature of from about 225 C. to about 500 C. and at a pressurewithin the range of about 500 to about 5000 pounds per square inchgauge;

(d) separating the resulting reaction mixture to provide from the ahydrorefined liquid product and a catalyst-contain ing sludge;

(e) contacting the sludge with an organic solvent to dissolve theorganic-soluble matter contained in said sludge and combining theresulting solution with said-charge stock;

(f) treating the remaining portion of said sludge, at a temperatureWithin the range of from about 300 C. to about 500 C., with a solutionof from about 0.1% to about 25.0% by weight of a sulfurous compoundselected from the group consisting of sulfur monochloride, sulfurdichloride and-a mixture ther of toconvert asphaltenes contained thereinto insoluble coke;

(g) separating the resulting insoluble coke from the thus-treatedsludge; and,

(h) combining the resulting coke-free remainder of said sludge,containing the aforesaid metal, with said petroleum crude oil andreacting the resultant colloidal suspension with hydrogen as aforesaid.

10. The process of claim 9 further characterized in that said heteropolyacid comprises silicomolybdic acid.

11. The process of claim 7 further characterized in that said carbonylcomprises molybdenum hexacarbonyl.

12. A process for hydrorefining a hydrocarbon charge stock containingasphaltenes which comprises the steps of:

(a) admixing said charge stock with at least one betadiketone complex ofa metal selected from the metals vide a hydrorefined liquid product anda catalystcontaining sludge;

(d) contacting the sludge with an organic solvent to dissolve theorganic-soluble material contained in said sludge and combining theresulting solution with said charge stock;

(e) treating the remaining portion of said sludge, at a temperatureWithin the range of from about 300 C. to about 500 C., with a solutionof from about 0.1% to about 25.0% by Weight of a sulfurous compoundselected from the group consisting of sulfur monochloride, sulfurdichloride and a mixture thereof to convert asphaltenes containedtherein to insoluble coke;

(f) separating the resulting insoluble coke from the thus-treatedsludge; and,

(g) combining the resulting coke-free remainder of said sludge,containing the aforesaid metal, with said hydrocarbon charge stock andreacting the resultant colloidal suspension with hydrogen as aforesaid.

13. The process of claim 12 further characterized in that the mixture ofsaid charge stock and decomposed beta-diketone complex is reacted withhydrogen and added hydrogen sulfide at a temperature Within the range'of' from about 225 C. to about 500 C. and under a pressure of fromabout 500 to 5000 pounds per square inch gauge.

14. The process of claim 12 further characterized in that saidbeta-diketone complex comprises vanadyl'acetyl- :acet-onate.

15. The process of claim 12 further charcaterized in that saidbeta-diketone complex comprises molybdyl acetylacetonate.

16. The process of claim 9 further characterized in that said heteropolyacid comprises phosphomolybdic acid.

References Cited by the Examiner UNITED STATES PATENTS 3 ,l65,463 l/1965 Gleim et al .,208264 DELBERT E. GANTZ, Primary Examiner. S. P,JONES, Assistant Examiner.

1. A REGENERATIVE PROCESS FOR HYDROREFINING A HYDROCARBON CHARGE STOCKCONTAINING ASPHALTENES WHICH COMPRISES THE STEPS OF: (A) ADMIXING SAIDCHARGE STOCK WITH AT LEAST ONE ORGANO-METALLIC COMPOUND OF A METALSELECTED FROM THE METALS OF GROUP VI-B HAVING AN ATOMIC NUMBER GREATERTHAN 24, AND GROUP V-B OF THE PERIODIC TABLE; (B) DECOMPOSING SAIDORGANO-METALLIC COMPOUND IN SAID CHARGE STOCK AND REACTING THE RESULTINGCOLLOIDAL SUSPENSION WITH HYDROGEN; (C) SEPARATING THE RESULTINGREACTION MIXTURE TO PROVIDE A HYDROREFINED LIQUID PRODUCT AND ACATALYSTCONTAINING SLUDGE; (D) CONTACTING THE SLUDGE WITH AN ORGANICSOLVENT TO DISSOLVE THE ORGANIC-SOLUBLE MATERIAL CONTAINED IN SAIDSLUDGE AND COMBINING THE RESULTING SOLUTION WITH SAID CHARGE STOCK; (E)TREATING THE REMAINING PORTION OF SAID CATALYST-CONTAINING SLUDGE AT ATEMPERATURE OF FROM ABOUT 100* C. TO ABOUT 500*C. WITH A SULFUROUSCOMPOUND SELECTED FROM THE GROUP CONSISTING OF SULFUR MONOCHLORIDE,SULFUR DICHLORIDE AND A MIXTURE THEREOF TO CONVERT ASPHALTENES CONTAINEDTHEREIN TO INSOLUBLE COKE; (F) SEPARATING THE RESULTING INSOLUBLE COKEFROM SAID SLUDGE; AND, (G) ADMIXING THE REMAINDER OF SAID SLUDGE,CONTAINING THE AFORESAID METAL, WITH SAID CHARGE STOCK.